Process of extracting soluble albumen from milk.



Patented July 26, 1904.

UNITED-STATES PATENT Orrrcic.

CHARLES LEIVIS, OF TORONTO, CANADA.

PROCESS OF EXTRACTING SOLUBLE ALBUWIEN FROM MILK.

SPECIFICATION forming part of Letters Patent No. 765,898, dated July 26,1904;;

Application filed November 14, 1902 T0 to whom, it may concern:

Be it known that I, CHARLES LEWIS, chemist, a citizen of the Dominion ofCanada, and a resident of the city of Toronto, in the county of York andProvince of Ontario, Canada, have invented or discovered a new anduseful manufacture or composition of matter consisting in an Improvementin Processes of Extracting Soluble Albumen from Milk for Use as aConcentrated Food, of which the following is a specification.

My invention relates to the manufacture of soluble albumen from milk;and its novelty consists in the several successive steps of the processemployed and in the product resulting therefrom.

In carrying out my process I first take sweet clean milk and remove thefat therefrom in any well-known manner, preferably in a creamseparator.This gives, in effect, skim-milk. I then add to the skim-milk a suitablequantity of grain alcohol until precipitation of the albumen has ceased.This can best be ascertained by filtering a small sample and addingclear alcohol to the filtrate. Of course any other of the tests foralbumen may be employed; but the one suggested is simple and practical.If the process is being carried out in a commercial way, this stepshould take place in a large tank holding several hundred gallons andunder conditions adapted to exclude the air in order to prevent theundue evaporation of the alcohol. The precipitate, which is in the formof casein, is next separated from the remaining liquid. This can bestbe'accomplished by straining in the first place and in the second placeby the application of heat to drive off the alcohol not rcmoved by thepurely mechanical means. There will always be some water developed fromthe milk, and after the bulk of the liquid has been removed by strainingI have found it advisable to add a small proportion of strong alcoholbefore heating. This constricts the curd to a certain extent and makesit more readily driable.

The drying can best be done in drying-closets of suitable size and formthrough which there is caused constantly to pass a current of air at atemperature of about 14:8 Fahrenheit,

Serial No. 131,333. (No specimens.)

cause if it does the precipitated albumen is apt to become insoluble, orat least insoluble in the gastric juice of the human stomach. When thealbumen or casein is thus dried, it will consist of a toughhorny masswhich must be converted into a finely-divided state. This is preferablybest accomplished by grinding it in a rollermill having both plain andcorrugated rolls. As some of the alcohol is apt to be entrained in thehorny precipitate, it is well to conduct the grinding operation in thepresence of a current of hot air, which will carry off any alcohol soentrained and which will be released during this operation and at anyrate to cause a current of hot air to be passed over the powder aftergrinding. The ground albumen is then ready for use. It may be takenmixed with water or milk or in beef-tea, cocoa, or other hot liquid,provided the temperature of such fluid does not exceed 150 I am wellaware that,speaking in general terms, it has long been known thatalcohol when added to a fluid containing albumen will sometimesprecipitate it. been taken of this reaction to employ it as a test forthe presence of albumen in urine, although this reaction is not veryreliable, be

cause urates are frequently precipitated as state is taken into thestomach the albumen or casein is curded by the pepsin in the stomachalong with the other gastric fluids; but when the casein has beenremoved from the milk by precipitation with alcohol and then dried andredissolved in water then it is no longer curded by the pepsin of thestomach. In other words, I have converted the casein from an insolubleinto a soluble form and that, too, without losing any of its foodAdvantage has

